1 Introduction Since the early of 1980’s,the studies of soft X-ray and EUV optics have been implemented in CIOMP (Changchun Institute of Optics,Fine Mechanics and Physics).So far,the research system of soft X-ray an...1 Introduction Since the early of 1980’s,the studies of soft X-ray and EUV optics have been implemented in CIOMP (Changchun Institute of Optics,Fine Mechanics and Physics).So far,the research system of soft X-ray and EUV optics has been founded including sources,ra- diometry,testing and manufacturing of the super smooth mirror and multilayer coating mirror fabrication.Based on the above technologies,we started to develop the soft X-ray and EUV optical system such as a space EUV solar telescope and a EUV imager.展开更多
This article describes a novel configuration design for a re-imaging off-axis catadioptric space infrared optical system,and in order to satisfy the signal noise ratio requirements of the system,the stray light of the...This article describes a novel configuration design for a re-imaging off-axis catadioptric space infrared optical system,and in order to satisfy the signal noise ratio requirements of the system,the stray light of the system is necessary to analyze and restrain. The optical system with a focal length of 1 200 mm,an entrance pupil diameter of 600 mm,an F-number of 2,a field of view of 3°× 0. 15°,a working wave band of 8 μm-10 μm,and the image quality of the optical system almost approach to diffraction limits in all field of view.Then the mathematical models of stray light are built,and the suppressive structure is established to eliminate the effect of stray light. Finally,TraceP ro is used to analyze and simulate stray light with and without the suppressive structure,and also get the results of the PST curves. The results indicate that appropriate optical system and suppressive structure can highly reduce the stray light of the space infrared optical system.展开更多
With the development of science, economy and society, the needs for research and exploration of deep space have entered a rapid and stable development stage. Deep Space Optical Network(DSON) is expected to become an i...With the development of science, economy and society, the needs for research and exploration of deep space have entered a rapid and stable development stage. Deep Space Optical Network(DSON) is expected to become an important foundation and inevitable development trend of future deepspace communication. In this paper, we design a deep space node model which is capable of combining the space division multiplexing with frequency division multiplexing. Furthermore, we propose the directional flooding routing algorithm(DFRA) for DSON based on our node model. This scheme selectively forwards the data packets in the routing, so that the energy consumption can be reduced effectively because only a portion of nodes will participate the flooding routing. Simulation results show that, compared with traditional flooding routing algorithm(TFRA), the DFRA can avoid the non-directional and blind transmission. Therefore, the energy consumption in message routing will be reduced and the lifespan of DSON can also be prolonged effectively. Although the complexity of routing implementation is slightly increased compared with TFRA, the energy of nodes can be saved and the transmission rate is obviously improved in DFRA. Thus the overall performance of DSON can be significantly improved.展开更多
When the light beam propagates in the atmosphere, the signal will be absorbed and scattered by the gas molecules and water mist in the atmosphere, which will cause the loss of power rate. The complex atmospheric envir...When the light beam propagates in the atmosphere, the signal will be absorbed and scattered by the gas molecules and water mist in the atmosphere, which will cause the loss of power rate. The complex atmospheric environment will produce a variety of adverse effects on the signal. The interference produced by these effects overlaps with each other, which will seriously affect the strength of the received signal. Therefore, how to effectively suppress the atmospheric turbulence effect in the random atmospheric turbulence channel, ensure the normal transmission of the signal in the atmospheric channel, and reduce the bit error rate of the communication system, is very necessary to improve the communication system. When processing the received signal, it is an important step to detect the transmitted signal by comparing the received signal with the threshold. In this paper, based on the atmospheric turbulence distribution model, the adaptive signal decision threshold is obtained through the estimation of high-order cumulant. Monte Carlo method is used to verify the performance of adaptive threshold detection. The simulation results show that the high-order cumulant estimation of atmospheric turbulence parameters can realize the adaptive change of the decision threshold with the channel condition. It is shown that the adaptive threshold detection can effectively restrain atmospheric turbulence, improve the performance of free space optical and improve the communication quality.展开更多
We examine theoretically the performance of an Hg0.77Cd0.23Te based p-n photodetector/HFET optical receiver due to its possible application at 10.6 μm free space optical communication system at high bit rate.A rigoro...We examine theoretically the performance of an Hg0.77Cd0.23Te based p-n photodetector/HFET optical receiver due to its possible application at 10.6 μm free space optical communication system at high bit rate.A rigorous noise model of the receiver has been developed for this purpose.We calculate the total noise and sensitivity of the receiver.The front-end of the receiver exhibits a sensitivity of -45 dBm at a bit rate of 1 Gb/s and -30 dBm at a bit rate of 10 Gb/s,and the total mean-square noise curren t〈i2n〉=5×10-15 A2 at a bit rate of 1 Gb/s an d〈i2n〉 =10-12 A2 at a bit rate of 10 Gb/s,and a 3-dB bandwidth of 10 GHz.展开更多
With the increasing demand for space optical communication security, space chaotic optical communication has attracted a great amount of attention. Compared with traditional space optical communication, a chaotic opti...With the increasing demand for space optical communication security, space chaotic optical communication has attracted a great amount of attention. Compared with traditional space optical communication, a chaotic optical communication system has a higher bit error rate(BER) for its complex system design. In order to decrease the BER of space chaotic optical communication systems, we introduce two diffractive optical elements(DOEs)at a transmitting terminal(Tx). That is because the commonly used reflective optical antenna at Tx blocks the central part of the transmission beam, which leads to a great amount of power consumption. Introducing the DOEs into the optical subsystem at Tx can reshape the transmission beam from a Gaussian distribution to a hollow Gaussian distribution so that the block of the secondary mirror in the reflective optical antenna can be avoided. In terms of the DOE influence on communication quality, we give a BER model based on a minimumshift-key(MSK) space uplink chaotic optical communication system to describe the DOE function. Based on the model, we further investigate the effect of the DOEs through analyzing the BER relationship versus basic system parameters based on the BER model. Both different mismatch conditions of chaotic systems and different atmospheric turbulence conditions are considered. These results will be helpful for the scheme design of space uplink chaotic optical communication systems.展开更多
Free-space optical communication and space optical information network offer many more superiorities over optical fiber,RF,or microwaves communication techniques,with higher data transfer rate,smaller platforms to lau...Free-space optical communication and space optical information network offer many more superiorities over optical fiber,RF,or microwaves communication techniques,with higher data transfer rate,smaller platforms to launch and lower costs.A comprehensive overview on the architectures of the space high-speed optical information network was provided.In fundamental system,networking approach and operation mechanisms of the space optical information network were fully emphasized to be discussed a lot.The interactions of light waves and microwave network have been outlined.A blueprint for space optical information network technology is presented to be used in various communication fields in the future.展开更多
文摘1 Introduction Since the early of 1980’s,the studies of soft X-ray and EUV optics have been implemented in CIOMP (Changchun Institute of Optics,Fine Mechanics and Physics).So far,the research system of soft X-ray and EUV optics has been founded including sources,ra- diometry,testing and manufacturing of the super smooth mirror and multilayer coating mirror fabrication.Based on the above technologies,we started to develop the soft X-ray and EUV optical system such as a space EUV solar telescope and a EUV imager.
基金Sponsored by the National High Technology Research and Development Program of China(Grant No.863-2-5-1-13B)
文摘This article describes a novel configuration design for a re-imaging off-axis catadioptric space infrared optical system,and in order to satisfy the signal noise ratio requirements of the system,the stray light of the system is necessary to analyze and restrain. The optical system with a focal length of 1 200 mm,an entrance pupil diameter of 600 mm,an F-number of 2,a field of view of 3°× 0. 15°,a working wave band of 8 μm-10 μm,and the image quality of the optical system almost approach to diffraction limits in all field of view.Then the mathematical models of stray light are built,and the suppressive structure is established to eliminate the effect of stray light. Finally,TraceP ro is used to analyze and simulate stray light with and without the suppressive structure,and also get the results of the PST curves. The results indicate that appropriate optical system and suppressive structure can highly reduce the stray light of the space infrared optical system.
基金supported by National Natural Science Foundation of China (61471109, 61501104 and 91438110)Fundamental Research Funds for the Central Universities ( N140405005 , N150401002 and N150404002)Open Fund of IPOC (BUPT, IPOC2015B006)
文摘With the development of science, economy and society, the needs for research and exploration of deep space have entered a rapid and stable development stage. Deep Space Optical Network(DSON) is expected to become an important foundation and inevitable development trend of future deepspace communication. In this paper, we design a deep space node model which is capable of combining the space division multiplexing with frequency division multiplexing. Furthermore, we propose the directional flooding routing algorithm(DFRA) for DSON based on our node model. This scheme selectively forwards the data packets in the routing, so that the energy consumption can be reduced effectively because only a portion of nodes will participate the flooding routing. Simulation results show that, compared with traditional flooding routing algorithm(TFRA), the DFRA can avoid the non-directional and blind transmission. Therefore, the energy consumption in message routing will be reduced and the lifespan of DSON can also be prolonged effectively. Although the complexity of routing implementation is slightly increased compared with TFRA, the energy of nodes can be saved and the transmission rate is obviously improved in DFRA. Thus the overall performance of DSON can be significantly improved.
文摘When the light beam propagates in the atmosphere, the signal will be absorbed and scattered by the gas molecules and water mist in the atmosphere, which will cause the loss of power rate. The complex atmospheric environment will produce a variety of adverse effects on the signal. The interference produced by these effects overlaps with each other, which will seriously affect the strength of the received signal. Therefore, how to effectively suppress the atmospheric turbulence effect in the random atmospheric turbulence channel, ensure the normal transmission of the signal in the atmospheric channel, and reduce the bit error rate of the communication system, is very necessary to improve the communication system. When processing the received signal, it is an important step to detect the transmitted signal by comparing the received signal with the threshold. In this paper, based on the atmospheric turbulence distribution model, the adaptive signal decision threshold is obtained through the estimation of high-order cumulant. Monte Carlo method is used to verify the performance of adaptive threshold detection. The simulation results show that the high-order cumulant estimation of atmospheric turbulence parameters can realize the adaptive change of the decision threshold with the channel condition. It is shown that the adaptive threshold detection can effectively restrain atmospheric turbulence, improve the performance of free space optical and improve the communication quality.
文摘We examine theoretically the performance of an Hg0.77Cd0.23Te based p-n photodetector/HFET optical receiver due to its possible application at 10.6 μm free space optical communication system at high bit rate.A rigorous noise model of the receiver has been developed for this purpose.We calculate the total noise and sensitivity of the receiver.The front-end of the receiver exhibits a sensitivity of -45 dBm at a bit rate of 1 Gb/s and -30 dBm at a bit rate of 10 Gb/s,and the total mean-square noise curren t〈i2n〉=5×10-15 A2 at a bit rate of 1 Gb/s an d〈i2n〉 =10-12 A2 at a bit rate of 10 Gb/s,and a 3-dB bandwidth of 10 GHz.
基金supported by Joint Funds of Space Science and Technology(No.6141B060307)Suzhou Technology Innovative for Key Industries Program of China(No.SYG201729)+2 种基金National Natural Science Foundation of China(No.61205045)Fundamental Research Funds for the Central Universities(No.021314380152)Six Talent Peaks Project in Jiangsu Province(No.KTHY-003)
文摘With the increasing demand for space optical communication security, space chaotic optical communication has attracted a great amount of attention. Compared with traditional space optical communication, a chaotic optical communication system has a higher bit error rate(BER) for its complex system design. In order to decrease the BER of space chaotic optical communication systems, we introduce two diffractive optical elements(DOEs)at a transmitting terminal(Tx). That is because the commonly used reflective optical antenna at Tx blocks the central part of the transmission beam, which leads to a great amount of power consumption. Introducing the DOEs into the optical subsystem at Tx can reshape the transmission beam from a Gaussian distribution to a hollow Gaussian distribution so that the block of the secondary mirror in the reflective optical antenna can be avoided. In terms of the DOE influence on communication quality, we give a BER model based on a minimumshift-key(MSK) space uplink chaotic optical communication system to describe the DOE function. Based on the model, we further investigate the effect of the DOEs through analyzing the BER relationship versus basic system parameters based on the BER model. Both different mismatch conditions of chaotic systems and different atmospheric turbulence conditions are considered. These results will be helpful for the scheme design of space uplink chaotic optical communication systems.
基金supported by Excellent Satellite Optical Communications Team in Harbin Institute of Technology.
文摘Free-space optical communication and space optical information network offer many more superiorities over optical fiber,RF,or microwaves communication techniques,with higher data transfer rate,smaller platforms to launch and lower costs.A comprehensive overview on the architectures of the space high-speed optical information network was provided.In fundamental system,networking approach and operation mechanisms of the space optical information network were fully emphasized to be discussed a lot.The interactions of light waves and microwave network have been outlined.A blueprint for space optical information network technology is presented to be used in various communication fields in the future.